I bought just the thin metal printed part, not the mount as well. I got the old one off by heating with a hair dryer and then teasing a corner up with a craft knife, .then steadily pulling and heating until it was all off Laquering them is supposed to slow fading down by filtering out the UV. I went over mine with some cheap clear nail varnish and so far so good. I do also keep the car under a cover as well though.
Oh,and clean thoroughly with white spirit before fitting the new one.